The handler messages (examples:
00:0017:00000:00433:2015/12/18 06:30:00.80 kernel [Handler pc: 0x00000001007903c4 hdl_stack installed by the following function:-]
00:0017:00000:00433:2015/12/18 06:30:00.81 kernel [Handler pc: 0x0000000100899ce8 s_handle installed by the following function:-]
are callback routines that are registered to handle errors that require more than trivial processing.
These entries showing them being installed generally aren't of any interest. However, an error
happening while executing a handler (as an example, s_handle appearing in the stack by itself without an "installed by" text) would be a serious issue.
-bret